Loadstar 16/016.d81/t.lk.conway's li

Text File | 2022-08-26 | 5KB | 287 lines

     About Conway's Game of Life
     ===== ======== ==== == ====

     written by: Joel Ellis Rea
            for: COMAL Corner


  This program is written as a COMAL

Kernal-compatible LIST file.  That

means you must have either COMAL 0.14

on disk (available from Loadstar), or

COMAL 2.0 on cartridge (available from

Commodore or the COMAL User's Group,

USA).  Since it is a LIST (SEQ) file,

it must be ENTERed, not LOADed, into

memory.  Just type (while in COMAL

with this disk in the drive):



   NEW   _ REQUIRED for 0.14,
           optional for 2.0!

   ENTER"LK.CONWAY'S LIFE"

   < Insert formatted disk now >

   SAVE"C.CONWAY'S LIFE"  _ 0.14, OR
   SAVE"C2.CONWAY'S LIFE" _ 2.0.


   From then on, you may LOAD and RUN

the program in a single step simply by

typing:


   CHAIN"C.CONWAY'S LIFE"  _ 0.14

                - OR -

   RUN"C2.CONWAY'S LIFE"   _ 2.0


from the appropriate COMAL.


   This program is an implementation

of a mathematical simulation invented

by mathematician John Conway.  He

called it "LIFE", because by using 3

simple rules, he could simulate the

growth of colonies of hypothetical

single-celled organisms.  These cells

are arranged in a rectangular (X-Y)

coordinate system (i.e. rows and col-

umns).  The rules are:


   #1.  All births and deaths occur
        simultaneously in a given
        generation.

   #2.  A "live" cell with exactly
        2 or 3 neighbors will survive
        to the next generation.  All
        others will "die" (either from
        isolation or overcrowding).

   #3.  An empty "cell" with exactly
        3 neighbors will become a
        "live" cell in the next gen-
        eration.


   That's it!  A "neighbor" is defined

as a "live" cell adjacent to the cell

in question, either horizontally,

vertically or diagonally.  Thus, each

cell may have from 0 to 8 neighbors!


   From these simple rules and a sim-

ple starting pattern, very complex and

beautiful patterns may form over the

course of succeeding generations.

From a particular starting pattern,

one of the following may happen:


   #1.  The colony will eventually
        die out completely

   #2.  The colony will stabilize
        into a cycling pattern.  The
        cycle may have a period of 1,
        and therefore not appear to
        change at all, or may have a
        very large period, in which
        case a human might not notice
        the cycling!

   #3.  The colony will change and
        grow forever, never dying out
        and never cycling (repeating).
        No pattern has been found that
        does this, but it has not been
        proven mathematically impos-
        sible!


   If a pattern is asymmetrical, it

will tend to become symmetrical.  Once

it becomes symmetrical, it can never

lose its symmetry.  (Theoretically,

that is.  In real "life" and this pro-

gram, the "world" has borders!)


   When the program starts, you will

have a blank screen and a circular

"cursor" that you may move with the

arrow keys, or "A" for up, "Z" for

down, "<" for left and ">" for right.

Pressing SPACE will place a dot (live

cell) at that spot if empty, or re-

move a live cell.  Press RETURN when

done entering your starting pattern

and the program will commence.


   This program actually uses the text

screen and the color memory for work-

ing storage.  There are no "arrays" in

memory keeping track of the cells and

their neighbors.  The color of a given

cell reflects how many neighbors it

has.  Thus, a RED cell has 2 neighbors

(RED = color 2), and thus will survive

to the next generation.  At the begin-

ning of each generation, all cells are

set to BLACK (color 0).


   The program does not actually count

how many neighbors each cell has.  In-

stead, it takes each "live" cell, and

increments the color of each surround-

ing cell, thus exerting a "neighborly"

influence on the surrounding cells!


   Here are some good starting pat-

terns to try:


                **
               **    "R Pentomino"
                *

R Pentomino comes quite close to ful-

filling result #3 -- infinite growth!

It has been observed to have a cycle

period well over 1000!


               ***
                *
                *
                *   "I-Beam"
                *
                *
               ***


I-Beams produce beautiful bi-symmetri-

cal patterns.  These patterns vary ac-

cording to the height of the central

beam, and whether said beam has an odd

or even number of dots!


              *     *
               *   *
                * *
                 *    "Big X"
                * *
               *   *
              *     *

Big X's produce lovely poly-symmetri-

cal patterns.  These vary on the size

of the X, and whether the two "arms"

meet at one dot (as above), or four

(like this:

                *  *
                 **
                 **
                *  * )



  Because this program is written in

COMAL, you cannot RUN it from the

LOADSTAR environment.  The program is

on Side 2 of this issue.  It is saved

under the name of LK.CONWAY'S LIFE.


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